Residual charge without enough to power the laptop can cause it to power down even when charged and charging.

Remove the battery and unplug the laptop then hold the power button down for 5 seconds to remove any residual charge. After this replace the battery, attach the charger and then turn on. If this does not help you may have to replace the battery.

Even a brand-new laptop can suffer from overheating without proper care. Avoid running the laptop for extended periods on soft surfaces, as these may fold and cover the fan vent. If the laptop begins to overheat for whatever reason, shut it off and let it sit on a cool, flat surface.

If the laptop overheats frequently without obvious cause, try spraying compressed air into the vents in the top right corner of the underside of the laptop. You may also consider purchasing a laptop cooling pad. Compressed air canisters and laptop cooling pads can be bought at any major electronics store.

When the laptop has been running at a high temperature for an extended period of time, the fix could be to take apart the computer according to Dell's service manual for the D630 (PDF) and clean all dust and debris out of the fan assembly and the heatsink assembly, and putting it all back together with new thermal paste on the processor, as well as new thermal pad(s) on the Nvidia-branded GPU (if applicable) and the chipset. In one case of overheating, this method fixed the issue entirely, although with about three hours of work.

Make sure you have a good antivirus program and run it regularly this will reduce the stress on your computer's temporary memory. Also routine removal of unused files or internet history will increase this effect.

“if you have too many programs running it can cause you computer to run slow”

If possible safely close all open programs and restart. If this is not possible manually restart you computer by pressing and holding the power button. Then when the system restarts check to see if the issue is still present

“the screen looks dull with a grey tone over it making it harder than normal for you to use your computer”

If the screen is dim, try using the keyboard's function keys to raise the brightness. To do this, press the blue "Fn" key (next to the left "Ctrl" button) and Up/Down arrow keys to either raise or lower the brightness. Also you can go into settings and adjust the power save mode as it may be causing your screen to dim after a specific length of time. If this fails, the screen maybe have to be replaced; see our screen installation guide here.

If there are tears or lines across the display, the screen's connector may be loose. See our screen installation guide to reset the connector here.

If the screen has dead pixels, there is little that can be done to fix it besides replacing the screen. If the dead pixels become intolerable, you can replace the screen by following our screen installation guide found here.

“this is if you can hear the computer running and the indication lights on the top are lit but the screen remains blank or has a faint black glow.”

Check battery by pressing the button located at the bottom and check for at least 2 green lights. If you do see the lights turn off the computer and then back on, when restarting have the computer open in safe mode if the option is given. If the problem still persist, try pressing the blue "Fn" key (next to the left Ctrl key) and F8. If this fails, try pressing the Windows key and "P". If this also fails, the screen cable may be loose or the screen itself may have to be replaced; see our helpful screen installation guide here.